Government requests for the mass disclosure of every caller who connected to a particular cellphone tower have spiked during the first half of 2017, according to Verizon’s latest transparency report.
Law enforcement seek so-called tower dumps to try to identify a suspect in a crime, compelling tower operators to provide the phone numbers of all devices that connected to a specific tower during a given period of time.
“This tool is being used much frequently by law enforcement,” Verizon said in the report.
Verizon has received approximately 8,870 warrants or court orders for cell tower dumps in the first half of this year — a huge increase over 2013, when the government sought only 3,200 dumps across the whole of that year. In 2016, the total figure was 14,630.
Law enforcement demands for customer data totaled at 138,773 for the first half of the year — relatively steady with six-month segments over the past two years. Verizon rejected around 3 percent of requests, granting around 68,000 subpoenas, 700 wiretap demands and about 4,000 “trap and trace” orders that let investigators see what phone numbers are calling a target in real time.
The company said it hands over the content of customers’ communications “relatively infrequently” — only when the government has obtained a warrant establishing probable cause. Verizon received 4,436 warrants for stored content during the first half of 2017, according to the report.
The number of national security letters received by the company — secret warrant-like requests for information made by the FBI in national security matters — appears to have held relatively steady.
Companies are permitted by federal law to disclose the number of NSLs they receive in bands of 500; Verizon for the past four six-month periods has received between one or zero and 500 NSLs.